Device and method for improved tennis racket damping and weight adjustment

ABSTRACT

The present application relates to devices and methods for adjusting the weight of a racket using variably weighted racket damping devices.

CROSS-REFERENCE TO RELATED APPLICATION AND INCORPORATION BY REFERENCE

This application claims priority to U.S. Provisional Application 61/647,420 filed May 15, 2012, entitled DEVICE AND METHOD FOR IMPROVED TENNIS RACKET DAMPING AND WEIGHT ADJUSTMENT, which is hereby incorporated by reference in its entirety.

BACKGROUND

1. Field

Embodiments disclosed herein relate generally to systems, devices, and methods for damping vibrations and adjusting the weight of a tennis racket.

2. Description of the Related Art

Handheld sports rackets, such as tennis rackets, have a handle and an oval frame extending from the handle. The handle includes a grip by which the player can hold the racket. The racket includes two intersecting sets of parallel strings attached to and suspended from the frame, creating a striking surface or face. One set of strings extends generally parallel to the handle of the racket and may be called the longitudinal strings, while the other set of strings extends generally transversely to the handle and may be called the transverse strings. Vibrations are produced in the racket when a player strikes a ball with the strings of the racket. The vibrations begin at the point of contact between the strings and the ball and the vibrations propagate through the strings to the frame of the racket. When a player strikes the ball with the center of the face of the racket, the vibrations are minimal. The vibrations can be substantial when the ball strikes the strings off of center of the face of the racket or when the ball strikes the frame of the racket. Initially, large vibrations disseminate from the point of contact on the strings, followed by a series of smaller vibrations which eventually die out with time. Such vibrations are transmitted generally along the transverse and longitudinal strings of the racket to the frame, which surrounds and secures the strings in place. The vibration can travel from the frame down to the racket handle and grip and through to the hand and arm of the player. Extensive periods of racket-induced vibrations can cause or exacerbate a “tennis elbow” injury or other such injuries in a player. It is therefore important to reduce such vibrations both for the comfort and protection of the player.

Also important to the comfort, performance, and safety of a tennis player is the use of a correctly weighted tennis racket. Tennis rackets can be purchased in different sizes and weights. A player of a certain skill level may prefer a racket of a certain weight or weight distribution. As a player's skill level changes, his or her preference for the weight of the racket may also change. Furthermore, a player's preference for the weight of the racket may change even during a tennis match as he or she becomes increasingly tired or as the conditions during the match change or even based on the types of strokes the player would like to be hitting. Traditionally, modifying or adjusting the weight of a tennis racquet was difficult, laborious, expensive, and imprecise. Changing the weight of a racket can be particularly difficult during the middle of a tennis match. Traditional methods of racket weight adjustment involve cumbersome devices and prolonged methods of adding weight to either the frame or the handle of the racket. To avoid such difficulties, tennis players often purchase a new, differently weighted racket instead. Purchasing a new racket of a different weight, or carrying multiple rackets of different weights, is an expensive solution to this problem. Other solutions such as placing weights in handle of the racket or applying weighted tape on the frame of the racket have proven cumbersome and imprecise. Applying weight to the handle or the frame of the racket can also have the adverse impact of unintentionally modifying the existing weight distribution in the racket.

Lacking in the prior art are methods, systems, and devices to successfully damp the vibrations in a tennis racket as well as allow for rapid adjustment of the weight of the racket without sacrificing stability, performance, comfort, playability, and safety.

SUMMARY

The present disclosure relates to a vibration damping device for use in a racket, having a shell composed of a damping material. The vibration damping device can also include a core fixedly positioned in the shell. The shell can be made of a rubberized material, which more specifically can be a rubber, a foam, an elastomeric polymer, a rubberized polymer, a thermoplastic polymer, a ceramic material, or a combination thereof.

In certain aspects of the disclosure, the core can be encased in the shell. The shell contain can include a gap in it and the core can have a shape that corresponds to the shape of the gap and can be positioned in the gap of the shell. The core can be made of a metal, an alloy, a foam, an elastomeric polymer, a thermoplastic polymer, a ceramic material, or combinations thereof.

The total weight of the vibration damping device can be between 3 g and 10 g. The shell can have an indentation circumventing the outside of it. The vibration damping device can be sized to fit between at least two strings on a racket such that the strings are positioned in the indentation.

The present disclosure also relates to a vibration damping device for use in a racket having a shell composed of a damping material and an insert releasably connected to the shell. The shell can have a bore through it and the insert can fit into the bore of the shell to secure the insert in the shell. In certain embodiments, the insert can have a cylindrical shape.

The present disclosure also relates to a kit having a plurality of vibration damping devices, such that each vibration damping device has a shell made of a damping material and has a core fixedly positioned in the shell and at least two of the vibration damping devices in the kit are of a different weight. In certain embodiments, each of the plurality of vibration damping devices in the kit is of the same approximate size and shape. The core of at least one vibration damping device can be a metal. The core of each vibration damping device in the kit can be a different composition. In the kit at least one vibration damping device can have a total weight of approximately 5 g or greater.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is top plan view of a tennis racket provided with a non-limiting example of a vibration damping device.

FIG. 2A is a perspective view of a non-limiting example of a vibration damping device according to an embodiment of the disclosure.

FIG. 2B is a perspective view of a non-limiting example of a rubberized shell according to an embodiment of the disclosure.

FIG. 3A is a perspective view of a non-limiting example of a vibration damping device according to an embodiment of the disclosure.

FIG. 3B is a cross-sectional side view of the device taken along line 3B of FIG. 3A.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS

In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented herein. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the Figures, can be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which are explicitly contemplated and make part of this disclosure.

The disclosure provided herein includes devices and methods for quickly and/or accurately modifying the weight of a tennis racket. In some aspects, this can be done without altering the weight distribution of the racket. Also based on the disclosure herein, the weight of the racket can be modified inexpensively compared with existing methods and devices and compared with having to purchase, try out, and carry multiple rackets of varying weight. The disclosure provides these improvements by combining a vibration damping device with a weight adjustment device to make for an inexpensive, easily adjustable, and accurate weight adjustment device in order to maintain stability, performance, comfort, playability, and safety of the player's racket.

Each player of a racket sport has a unique swing pattern and style of play. That said, individual maximum performance during play is often a function of increased power and control of a shot. Power and control, however, can sometimes be competing priorities for a player. Power and control can be dictated by the player's swing velocity, which itself is a function of the racket weight. The disclosed improvements allow a player to easily and accurately adjust the weight of his or her racket in order to optimize the player's swing velocity, thereby improving performance during play.

Vibration damping devices can be placed in between, through, or around the strings of a tennis track to reduce the vibration produced by striking of the ball against the strings or frame of the racket. FIG. 1 is top plan view of a tennis racket provided with a vibration damping device. As seen in FIG. 1, a tennis racket 2 can be comprised of a frame 10 with a handle 20 extending from the frame 10. The handle 20 can also include a grip 30 by which the tennis player can hold onto the racket. Attached to the frame are two sets of strings that run perpendicular to one another other. One set of strings, the transverse strings 12, run in a direction transverse to a longitudinal axis and handle of the racket 2. Perpendicular to the transverse strings 12 are the longitudinal strings 14 which run in the direction parallel with the longitudinal axis and handle of the racket 2. As shown in FIG. 1, a vibration damping device 40 can be placed in the strings of the racket 2, to be positioned between two longitudinal strings 14 and either below the bottommost transverse string 12 a or alternatively positioned between two transverse strings 12, such as between transverse strings 12 a and 12 b.

The vibration damping device 40 shown in FIG. 1 is approximately spherical in shape. Other shapes and sizes of vibration damping devices are contemplated and within the scope of the present disclosure. For example, the vibration damping device 40 may also be square, oval, rectangular or cubic in shape. The vibration damping device 40 may be, for example, a round cylinder, an oval cylinder, a sphere, a cube, a non square or cubic polyhedron, or a shape corresponding to a specific brand's logo. As a further example, the device 40 may be, alternatively, a longer, thinner device such that when the device is inserted into the racket 2 it can run in a transverse direction and can be, for example, weaved or laced in and out of multiple longitudinal strings 14 at the bottom of the racket face 16. The vibration damping device 40 of the present disclosure can be provided with branding or sponsorship information, for example to match the brand of the player's tennis racket. Additionally, the vibration damping device 40 can be void of such branding. The device can include one or more indicators of the weight of the device, for example numerical, color, letter or other indicators.

An embodiment of the vibration damping device 40, regardless of the shape of the device 40, can include an indentation or channel circumventing the exterior of the vibration damping device 40. The indentation provides a structure to position the device between the longitudinal strings 14 and transverse strings 12. The indentation can be approximately the width of racket string and may be deep enough such that when the device 40 is placed into the racket strings the device 40 fits securely within the strings and does not easily become dislodged. In some embodiments, the width of the indentation also can be such that the strings fit tightly or securely within the indentation.

The disclosure herein provides methods and devices for adjusting the weight of a racket by adjusting the weight of the vibration damping device 40. FIG. 2A is a perspective view of a vibration damping device 40 according to an embodiment of the disclosure. The non-limiting example of a vibration damping device 40 in FIG. 2A is comprised of a rubberized shell 150 and an insert 160. The rubberized shell 150 can include an annular channel or indentation 154 at least partially circumventing the exterior of the rubberized shell 150. The annular indentation 154 may also fully circumvent the exterior of the rubberized shell 150. The rubberized shell 150 can be composed of one or more natural or synthetic rubberized polymers. While a “rubberized” shell is described herein, it should be understood that other damping materials can be utilized for the shell, such as, for example, various types of foam, elastomeric polymers, thermoplastic polymers, ceramic material, and other natural or synthetic materials, or any combination thereof. Damping materials can absorb and reduce the vibrational energy created when a ball strikes the racket 2.

The insert 160 may be composed of, for example, certain metals, alloys, foam, elastomeric polymers, thermoplastic polymers, ceramic material, and other natural or synthetic materials, or any combination thereof.

To implement the vibration damping device 40 shown in FIGS. 2A and 2B, one can place the rubberized shell 150 into the strings of the racket 2 between two longitudinal strings 14 and either below the bottom most transverse string 12 or between two transverse strings 12. Once in place, the rubberized shell 150 can be fitted with an insert 160 of a weight desired by the player.

FIG. 2B shows the rubberized shell 150 without the insert 160. Shown in FIG. 2B is an aperture or annular bore 156 running through the center of the rubberized shell 150, defined by an interior wall 152 of the rubberized shell 150. An insert 160 of a desired weight can be placed into the annular bore 156 in the rubberized shell 150. The insert 160 can have an exterior wall 162 that fits securely against the interior wall 152 of the rubberized shell 150. The 160 insert can have a mechanism for securing it removably or permanently to the rubberized shell 150. For example, the mechanism can be, or can include, one or more of a ridge, indentation, fastener, knob, or joint. It should be understood that FIG. 2B depicts one non-limiting example of a device with a removable weight or insert. Other configurations that utilize, for example, a rubberized (or other damping material, for example) shell or portion that contacts the racket strings, as well as one or more weighted inserts can be utilized in a vibration damping device 40. For example, the insert 160 can be removably or permanently attached to an outside portion of the rubberized shell 150.

In order to adjust the weight of the vibration damping device 40, and thus adjust the weight of the racket 2, a player can remove the insert 160 already in the rubberized shell 150 and replace it with an insert 160 of the different weight. The weight of different inserts 160 can be varied by maintaining the size of the insert 160 and using different material compositions with different densities for the insert. The weight of the insert 160 can also be varied by maintaining the material composition and varying the size of the insert 160. Furthermore, the weight of the insert can be varied by varying both the size of the insert 160 and the material composition.

If the weight of the inserts is varied by varying by the size of the inserts 160, a lighter weight insert 160 may be small enough to be set inside the annular aperture or bore 156, thus set below the top and bottom surfaces of the rubberized shell. A heavier insert 160 may be longer than a lighter weight insert 160 and thus may be set flush with the top and/or bottom surfaces of the rubberized shell 150 or may even extend beyond the top and/or bottom surfaces of the rubberized shell 150. In some instances the insert 160 may have a top and/or bottom that is below the top and/or bottom of the rubberized shell 150.

The ease with which an insert 160 can be replaced with a different insert provides a way for the player to easily adjust the weight of the racket. The player can know precisely how much weight is being added to the racket by knowing the precise weight of the inserted to be placed in the rubberized shell 150. Thus, changing the weight of the racket can be performed rapidly, easily, and precisely.

Multiple inserts 160, either of the same weight or each with a different but precisely measured weight can be packaged and sold together as a kit, along with or separate from the rubberized shell 150. Such a kit can allow a tennis player to adjust the weight of his or her racket as needed, according to his or her changing ability or changing conditions during or between tennis matches.

The weight of the insert 160 can be produced and used in weights varying from 0.5 g to 50 g. For example, an individual insert may weigh from about 0.5 g to about 100 g, for example, or any value there between. In some aspects an individual insert may weigh, for example, 0.5 g, 1 g, 2 g, 3 g, 4 g, 5 g, 6 g, 7 g, 8 g, 9 g, 10 g, 11 g, 12 g, 13 g, 14 g, 15 g, 16 g, 17 g, 18 g, 19 g, 20 g, 21 g, 22 g, 23 g, 24 g, 25 g, 26 g, 27 g, 28 g, 29 g, 30 g, 31 g, 32 g, 33 g, 34 g, 35 g, 36 g, 37 g, 38 g, 39 g, 40 g, 41 g, 42 g, 43 g, 44 g, 45 g, 46 g, 47 g, 48 g, 49 g, or 50 g. The inserts can be labeled or coded using numbers, letters, words, colors or other indicators of their weight and/or size, for example. Kits may include any combination of differently weighted inserts 160.

An embodiment of the vibration damping device 40 is shown in FIGS. 3A and 3B. FIG. 3A is a perspective view of a vibration damping device according to an embodiment of the disclosure. The vibration damping device 40 can include a rubberized shell 250 and an indentation 254 circumventing all or part of the exterior of the rubber shell 250. The indentation 254 provides one non-limiting example of the structure by which to position the device between the longitudinal strings 14 and transverse strings 12. The indentation 254 can be approximately the width of a racket string and may be deep enough such that when the device 40 is placed into the racket strings the device 40 fits securely within the strings and does not easily become dislodged. In some embodiments, the width of the indentation 254 also can be such that the strings fit tightly or securely within the indentation.

FIG. 3B is a cross-sectional side view of the device taken along line 3B of FIG. 3A. Shown in FIG. 3B is the rubberized shell 250 of the vibration damping device 40. Also shown in FIG. 3B is a core 260. The core 260 can be made of certain metals, alloys, polymers, or any combination thereof. The core 260 can be encased partially or entirely in an aperture or gap in the rubberized shell 250. The core 260 can be made to be a precise weight, such that when combined or encased in the rubberized shell, the total weight of the vibration damping device 40 of FIGS. 3A and 3B is of a known, precise weight.

To obtain vibration damping devices 40 of varying weights, the weight of the core 260 can be varied. For example, materials of different densities can be used for the core 260 to obtain a vibration damping device of a different weight, or the size of the core 260 can increased or decreased to vary the weight of the vibration damping device 40, or the type of material used as the core 260 can be varied to vary the weight of the vibration damping device 40. A vibration damping device 40 of a specific weight can be sold individually. Alternatively, multiple vibration damping devices 40, either of the same weight or each with a different but precisely measured weight can be packaged and sold together as a kit. It should be understood that any shape of shell 250 and/or core 260 can be utilized, not just the shapes and configuration depicted.

Vibration damping devices 40 disclosed herein can be produced and used in weights varying from 0.5 g to 50 g. For example, an individual vibration damping device may weigh from about 0.5 g to about 100 g or any value therebetween. 0.5 g, 1 g, 2 g, 3 g, 4 g, 5 g, 6 g, 7 g, 8 g, 9 g, 10 g, 11 g, 12 g, 13 g, 14 g, 15 g, 16 g, 17 g, 18 g, 19 g, 20 g, 21 g, 22 g, 23 g, 24 g, 25 g, 26 g, 27 g, 28 g, 29 g, 30 g, 31 g, 32 g, 33 g, 34 g, 35 g, 36 g, 37 g, 38 g, 39 g, 40 g, 41 g, 42 g, 43 g, 44 g, 45 g, 46 g, 47 g, 48 g, 49 g, or 50 g. Kits may include any combination of differently weighted vibration damping devices. The vibration damping device 40 can be labeled or coded using numbers, letters, words, colors or other indicators of their weight and/or size, for example.

The devices described above and depicted in the figures show the use of a single damping and/or weighting device being used with a racket. It should be understood that in some embodiments, multiple damping and/or weighting devices as described herein can be utilized. Also, FIGS. 2A, 2B, 3A, and 3B depict a shell with a single insert or core. Nonetheless, it should be understood that in some embodiments a shell can receive more than one insert or core, or can include receiving spaces (e.g., the annular bore 156 of FIG. 2B) for more than one insert or core, even if only one insert or core is used at times. The receiving space can be “capped” or “plugged” with a cover or plug that does not provide substantial weight to the device. Furthermore, in some embodiments the shell can be configured so that one or more inserts or cores is inserted or attached to the shell from a different approach or direction. For example, rather than attach the insert or core through the center of the shell perpendicular to the face 16 or plane of the racket 2, the insert or core can be inserted more or less parallel to the longitudinal strings (e.g., strings 14 of FIG. 1) into the bottom end or portion of the shell that when in place is closest to the handle. The insert or core can be placed or secured via any other suitable direction or orientation as well.

The foregoing description details certain embodiments of the systems, devices, and methods disclosed herein. It will be appreciated, however, that no matter how detailed the foregoing appears in text, the devices and methods can be practiced in many ways. As is also stated above, it should be noted that the use of particular terminology when describing certain features or aspects of the invention should not be taken to imply that the terminology is being re- defined herein to be restricted to including any specific characteristics of the features or aspects of the technology with which that terminology is associated. The scope of the disclosure should therefore be construed in accordance with the appended claims and any equivalents thereof

It will be appreciated by those skilled in the art that various modifications and changes may be made without departing from the scope of the described technology. Such modifications and changes are intended to fall within the scope of the embodiments, as defined by the appended claims. It will also be appreciated by those of skill in the art that parts included in one embodiment are interchangeable with other embodiments; one or more parts from a depicted embodiment can be included with other depicted embodiments in any combination. For example, any of the various components described herein and/or depicted in the Figures may be combined, interchanged, or excluded from other embodiments.

With respect to the use of any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to embodiments containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”

While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting. 

What is claimed is:
 1. A vibration damping device for use in a racket, comprising: a shell comprising a damping material; and a core fixedly positioned in the shell.
 2. The device of claim 1, wherein the shell comprises a rubberized material.
 3. The device of claim 2, wherein the rubberized material comprises a rubber, a foam, an elastomeric polymer, a rubberized polymer, a thermoplastic polymer, a ceramic material, or a combination thereof.
 4. The device of claim 1, wherein the core is encased in the shell.
 5. The device of claim 1, wherein the shell contains a gap therein.
 6. The device of claim 5, wherein the core has a shape corresponding to the shape of the gap and is positioned in the gap of the shell.
 7. The device of claim 1, wherein the core comprises a metal, an alloy, a foam, an elastomeric polymer, a thermoplastic polymer, a ceramic material, or combinations thereof.
 8. The device of claim 1, wherein the device has a total weight of between 3 g and 10 g.
 9. The device of claim 1, wherein the shell comprises an indentation circumventing the outside of the shell.
 10. The device of claim 9, wherein the device is sized to fit between at least two strings on a racket such that the strings are positioned in the indentation.
 11. A racket comprising the device of claim
 1. 12. A vibration damping device for use in a racket, comprising: a shell comprising a damping material; and an insert releasably connected to the shell.
 13. The device of claim 12, wherein the shell comprises a bore therethrough.
 14. The device of claim 13, wherein the insert fits into the bore of the shell that is configured to secure the insert to the shell.
 15. The device of claim 14, wherein the insert has a cylindrical shape and is positioned in the bore of the shell.
 16. A kit comprising a plurality of vibration damping devices, each vibration damping device comprising: a shell comprising a damping material; and a core fixedly positioned in the shell; wherein at least two of the vibration damping devices are of a different weight.
 17. The kit of claim 16, wherein each of the plurality of vibration damping devices is of the same approximate size and shape.
 18. The kit of claim 16, wherein the core of at least one vibration damping device comprises a metal.
 19. The kit of claim 16, wherein the core of each vibration damping device comprises a different composition.
 20. The kit of claim 16, wherein at least one vibration damping device has a total weight of approximately 5 g or greater. 